Three-phase ac reactor having external connection position change unit and manufacturing method thereof

ABSTRACT

A three-phase AC reactor according to an embodiment of the present invention includes three-phase coils that are not arranged in parallel, an input and output terminal block having an input and output unit having a parallel arrangement, and an external connection position change unit disposed between a coil end of each of the three-phase coils and the input and output terminal block to connect the coil end to the input and output terminal block.

This application is a new U.S. patent application that claims benefit ofJP 2016-141678 filed on Jul. 19, 2016, the content of 2016-141678 isincorporated herein by reference.

BACKGROUND OF THE INVENTION 1. Field of the Invention

The present invention relates to a three-phase AC reactor, and inparticular relates to a three-phase AC reactor that has an externalconnection position change unit disposed between coil ends of coils andan input and output terminal block.

2. Description of Related Art

Alternating current (AC) reactors are used in order to suppress harmoniccurrent occurring in inverters and the like, to improve input powerfactors, or to reduce inrush current to inverters. An AC reactor has acore made of a magnetic material and a coil formed around the outside ofthe core.

FIG. 1 shows the structure of a conventional three-phase AC reactor (forexample, Japanese Unexamined Patent Publication (Kokai) No.2009-283706). A conventional three-phase AC reactor 1000 includesthree-phase coils 101 a, 101 b, and 101 c aligned in the directions ofthe double-headed arrow of FIG. 1. The coils 101 a, 101 b, and 101 chave output terminals 210 a, 210 b, and 210 c, and input terminals 220a, 220 b, and 220 c, respectively. In the conventional three-phase ACreactor, as shown in FIG. 1, the three-phase coils are arranged(apposed) in parallel and in a linear manner, and each coil and itsinput and output terminals are aligned. Thus, it is easy to connect ageneral-purpose input and output terminal block having linearly arrangedinput and output terminals to the input and output terminals of thethree-phase AC reactor.

However, there are also three-phase AC reactors having three-phase coilsthat are arranged (apposed) neither in parallel nor in a linear mannerin recent years (for example, International Publication No.2012/157053). FIG. 2A is a perspective view of a conventional reactordevice, and FIG. 2B is a plan view of the conventional reactor device. Aconventional reactor device 2000 includes yoke cores 911 a and 911 b,three magnetic leg cores 931, three zero-phase magnetic leg cores 941,and three coils 921. The three coils 921 are disposed, for example, 120degrees apart from each other with respect to the central axis of theyoke core 911 a.

To connect a general-purpose input and output terminal block to such athree-phase AC reactor, bus bars or cables are required to connectbetween coil ends and the input and output terminal block. The coil endsthat are arranged (apposed) neither in parallel nor in a linear mannercause difficulty in connection to the general-purpose input and outputterminal block and connection to an external device. There are alsoconcerns about an increase in production man-hours and the occurrence ofoperation errors.

SUMMARY OF THE INVENTION

The present invention aims at providing a three-phase AC reactor that iseasily connected to an external device even if the three-phase coils arearranged (apposed) neither in parallel nor in a linear manner.

A three-phase AC reactor according to an embodiment of the presentinvention includes three-phase coils that are not arranged in parallelwith each other, an input and output terminal block having an input andoutput unit having a parallel arrangement, and an external connectionposition change unit disposed between a coil end of each of thethree-phase coils and the input and output terminal block so as toconnect the coil end to the input and output terminal block.

BRIEF DESCRIPTION OF THE DRAWINGS

The objects, features, and advantages of the present invention willbecome more apparent from the following detailed description of anembodiment, along with accompanying drawings. In the accompanyingdrawings:

FIG. 1 is a perspective view of a conventional three-phase AC reactor inwhich the three-phase coils are arranged in parallel;

FIG. 2A is a perspective view of a conventional three-phase AC reactorin which the three-phase coils are not arranged in parallel;

FIG. 2B is a plan view of a conventional three-phase AC reactor in whichthe three-phase coils are not arranged in parallel;

FIG. 3 is a perspective view of a three-phase AC reactor having anexternal connection position change unit according to an embodiment ofthe present invention;

FIG. 4 is a plan view of the three-phase coils constituting thethree-phase AC reactor according to the embodiment of the presentinvention;

FIG. 5A is a perspective view of an input and output terminal blockconstituting the three-phase AC reactor according to the embodiment ofthe present invention;

FIG. 5B is a perspective view of the external connection position changeunit constituting the three-phase AC reactor according to the embodimentof the present invention;

FIG. 5C is a perspective view of the three-phase coils constituting thethree-phase AC reactor according to the embodiment of the presentinvention;

FIG. 6A is a plan view of non-intersecting bus bars that constituteanother external connection position change unit according to theembodiment of the present invention;

FIG. 6B is a plan view of a mold unit, for molding the non-intersectingbus bars therein, that constitutes the external connection positionchange unit according to the embodiment of the present invention;

FIG. 7A is a perspective view of the non-intersecting bus bars thatconstitute the external connection position change unit according to theembodiment of the present invention;

FIG. 7B is a plan view of the non-intersecting bus bars that constitutethe external connection position change unit according to the embodimentof the present invention;

FIG. 7C is a plan view of three-phase coils for the external connectionposition change unit of the three-phase AC reactor according to theembodiment of the present invention;

FIG. 8A is a perspective view of intersecting bus bars that constitutethe external connection position change unit according to the embodimentof the present invention;

FIG. 8B is a plan view of the intersecting bus bars that constitute theexternal connection position change unit according to the embodiment ofthe present invention;

FIG. 8C is a plan view of the three-phase coils for the externalconnection position change unit of the three-phase AC reactor accordingto the embodiment of the present invention;

FIG. 9A is a plan view of the three-phase coils constituting thethree-phase AC reactor according to the embodiment of the presentinvention;

FIG. 9B is a plan view of the external connection position change unitconstituting the three-phase AC reactor according to the embodiment ofthe present invention;

FIG. 9C is a plan view of the input and output terminal blockconstituting the three-phase AC reactor according to the embodiment ofthe present invention;

FIG. 10A is a drawing showing the connection (by pressure welding usinga connector) between the three-phase coils and the external connectionposition change unit that constitute the three-phase AC reactoraccording to the embodiment of the present invention;

FIG. 10B is a drawing showing the connection (by pressure welding usinga connector) between the three-phase coils and the external connectionposition change unit that constitute the three-phase AC reactoraccording to the embodiment of the present invention;

FIG. 11A is a plan view of a coil end insertion slot of the externalconnection position change unit and a coil end according to theembodiment of the present invention;

FIG. 11B is a sectional view of the coil end insertion slot of theexternal connection position change unit and the coil end according tothe embodiment of the present invention;

FIG. 12A is a drawing showing the connection (by screwing) between theexternal connection position change unit and the input and outputterminal block according to the embodiment of the present invention;

FIG. 12B is a drawing showing the connection (by screwing) between theexternal connection position change unit and the input and outputterminal block according to the embodiment of the present invention;

FIG. 13A is a drawing in which the components of the three-phase ACreactor according to the embodiment of the present invention areexploded;

FIG. 13B is a perspective view showing the entire structure of thethree-phase AC reactor according to the embodiment of the presentinvention; and

FIG. 14 is a flowchart that explains a method for manufacturing thethree-phase AC reactor according to the embodiment of the presentinvention.

DETAILED DESCRIPTION OF THE INVENTION

A three-phase AC reactor according to the present invention will bedescribed below with reference to the drawings. FIG. 3 is a perspectiveview of a three-phase AC reactor 10 according to an embodiment of thepresent invention. FIG. 4 is a plan view of the three-phase coilsconstituting the three-phase AC reactor according to the embodiment ofthe present invention. The three-phase AC reactor 10 according to theembodiment of the present invention has three-phase coils (1 a, 1 b, and1 c), an input and output terminal block 2, and an external connectionposition change unit 3. The three-phase coils (1 a, 1 b, and 1 c) arelocated internally in a casing indicated by reference numeral 1.

As shown in FIG. 4, in the three-phase AC reactor according to theembodiment of the present invention, the three-phase coils (1 a, 1 b,and 1 c) are arranged (apposed) neither in parallel nor in a linearmanner. FIG. 5C is a perspective view of the three-phase coilsconstituting the three-phase AC reactor according to the embodiment ofthe present invention. The three-phase coils (1 a, 1 b, and 1 c) arelocated internally in the casing 1. The first coil 1 a has a firstoutput coil end 11 a and a first input coil end 12 a. The second coil 1b has a second output coil end 11 b and a second input coil end 12 b.The third coil 1 c has a third output coil end 11 c and a third inputcoil end 12 c. The coil ends are approximately equal in height with eachother. For example, the first coil 1 a may be an R-phase coil, thesecond coil 1 b may be an S-phase coil, and the third coil 1 c may be aT-phase coil. The “coil end” refers to an end of each coil.

As shown in FIG. 3, the input and output terminal block 2 has an inputand output unit (21 a, 21 b, 21 c, 22 a, 22 b, and 22 c) having aparallel and linear arrangement (apposition). In other words, a firstoutput terminal 21 a, a second output terminal 21 b, and a third outputterminal 21 c are arranged in a straight line, while a first inputterminal 22 a, a second input terminal 22 b, and a third input terminal22 c are arranged in another straight line. The two straight lines arearranged (apposed) in parallel and in a linear manner. Such anarrangement is here referred to as “apposition”.

FIG. 5A is a perspective view of the input and output terminal block 2constituting the three-phase. AC reactor according to the embodiment ofthe present invention. As described later, the first output terminal 21a is electrically connected to the first output coil end 11 a of thefirst coil 1 a through a bus bar 31 a. The first input terminal 22 a iselectrically connected to the first input coil end 12 a of the firstcoil 1 a through a bus bar 32 a. The second output terminal 21 b iselectrically connected to the second output coil end 11 b of the secondcoil 1 b through a bus bar 31 b. The second input terminal 22 b iselectrically connected to the second input coil end 12 b of the secondcoil 1 b through a bus bar 32 b. The third output terminal 21 c iselectrically connected to the third output coil end 11 c of the thirdcoil 1 c through a bus bar 31 c. The third input terminal 22 c iselectrically connected to the third input coil end 12 c of the thirdcoil 1 c through a bus bar 32 c.

FIG. 5B is a perspective view of the external connection position changeunit constituting the three-phase AC reactor according to the embodimentof the present invention. The external connection position change unit 3is disposed between each of the coil ends (11 a, 11 b, 11 c, 12 a, 12 b,and 12 c) of the three-phase coils (1 a, 1 b, and 1 c) and the input andoutput terminal block 2 so as to connect the coil ends to the input andoutput terminal block 2. The external connection position change unit 3includes the first output terminal bus bar 31 a, the first inputterminal bus bar 32 a, the second output terminal bus bar 31 b, thesecond input terminal bus bar 32 b, the third output terminal bus bar 31c, and the third input terminal bus bar 32 c, which are molded in aresin or the like. The first output terminal bus bar 31 a has oneterminal 33 a on the side of the first coil 1 a and the other terminalon the other side that extend in a vertical direction with respect to ahorizontal surface, and a portion between both of the terminals thatextends in a horizontal direction. The other bus bars have similarstructures.

The terminal 33 a of the first output terminal bus bar 31 a on the sideof the first coil 1 a is electrically connected to the first output coilend 11 a of the first coil 1 a. The terminal 34 a of the first inputterminal bus bar 32 a on the side of the first coil 1 a is electricallyconnected to the first input coil end 12 a of the first coil 1 a. Theterminal 33 b of the second output terminal bus bar 31 b on the side ofthe second coil 1 b is electrically connected to the second output coilend 11 b of the second coil 1 b. The terminal 34 b of the second inputterminal bus bar 32 b on the side of the second coil 1 b is electricallyconnected to the second input coil end 12 b of the second coil 1 b. Theterminal 33 c of the third output terminal bus bar 31 c on the side ofthe third coil 1 c is electrically connected to the third output coilend 11 c of the third coil 1 c. The terminal 34 c of the third inputterminal bus bar 32 c on the side of the third coil 1 c is electricallyconnected to the third input coil end 12 c of the third coil 1 c.

The terminal of the first output terminal bus bar 31 a on the side ofthe input and output terminal block 2 is electrically connected to thefirst output terminal 21 a. The terminal of the first input terminal busbar 32 a on the side of the input and output terminal block 2 iselectrically connected to the first input terminal 22 a. The terminal ofthe second output terminal bus bar 31 b on the side of the input andoutput terminal block 2 is electrically connected to the second outputterminal 21 b. The terminal of the second input terminal bus bar 32 b onthe side of the input and output terminal block 2 is electricallyconnected to the second input terminal 22 b. The terminal of the thirdoutput terminal bus bar 31 c on the side of the input and outputterminal block 2 is electrically connected to the third output terminal21 c. The terminal of the third input terminal bus bar 32 c on the sideof the input and output terminal block 2 is electrically connected tothe third input terminal 22 c.

FIG. 3 shows in perspective a connection state of the input and outputterminal block 2, the external connection position change unit 3, andthe three-phase coils (1 a, 1 b, and 1 c) shown in FIGS. 5A to 5C, whichconstitute the three-phase AC reactor according to the embodiment of thepresent invention. The external connection position change unit 3preferably has a structure which is detachable from the coil ends and aconnection unit of the input and output terminal block 2.

In the above embodiment, the bus bars constituting the externalconnection position change unit partly intersect with each other.However, not limited to this structure, the bus bars constituting theexternal connection position change unit may not intersect with eachother. FIG. 6A is a plan view of non-intersecting bus bars 31 thatconstitute the external connection position change unit 3 according tothe embodiment of the present invention. FIG. 6B is a plan view of amold unit 41 for molding the bus bars 31.

The bus bars 31 constituting the external connection position changeunit 3 include a first output terminal bus bar 301 a, a first inputterminal bus bar 302 a, a second output terminal bus bar 301 b, a secondinput terminal bus bar 302 b, a third output terminal bus bar 301 c, anda third input terminal bus bar 302 c, which are molded in a resin or thelike. The first output terminal bus bar 301 a has one terminal 303 a onthe side of the first coil 1 a and the other terminal on the other sidethat extend in a vertical direction with respect to a horizontalsurface, and a portion between both of the terminals that extends in ahorizontal direction. The other bus bars have similar structures. Theterminals 303 a, 303 b, and 303 c of the first to third output terminalbus bars 301 a, 301 b, and 301 c on the side of the first to third coils1 a, 1 b, and 1 c are connected to the output coil ends of the first tothird coils 1 a, 1 b, and 1 c, respectively, while the other terminalsthereof on the other side are connected to the input and output terminalblock 2. The terminals 304 a, 304 b, and 304 c of the first to thirdinput terminal bus bars 302 a, 302 b, and 302 c on the side of the firstto third coils 1 a, 1 b, and 1 c are connected to the input coil ends ofthe first to third coils 1 a, 1 b, and 1 c, respectively, while theother terminals thereof on the other side are connected to the input andoutput terminal block 2.

The mold unit 41 has a plurality of slots (41 a to 41 c, 42 a to 42 c,43 a to 43 c, and 44 a to 44 c). Reference numeral 41 a indicates aninsertion slot for a metal part of the terminal block or a protrusionslot of the bus bar 301 a (R-phase output). Reference numeral 41 bindicates an insertion slot for a metal part of the terminal block or aprotrusion slot of the bus bar 301 b (S-phase output). Reference numeral41 c indicates an insertion slot for a metal part of the terminal blockor a protrusion slot of the bus bar 301 c (T-phase output). Referencenumeral 42 a indicates an insertion slot for a metal part of theterminal block or a protrusion slot of the bus bar 302 a (R-phaseinput). Reference numeral 42 b indicates an insertion slot for a metalpart of the terminal block or a protrusion slot of the bus bar 302 b(S-phase input). Reference numeral 42 c indicates an insertion slot fora metal part of the terminal block or a protrusion slot of the bus bar302 c (T-phase input).

Reference numeral 43 a indicates an insertion slot of the coil end or aprotrusion slot of the bus bar 301 a (R-phase output). Reference numeral43 b indicates an insertion slot of the coil end or a protrusion slot ofthe bus bar 301 b (S-phase output). Reference numeral 43 c indicates aninsertion slot of the coil end or a protrusion slot of the bus bar 301 c(T-phase output). Reference numeral 44 a indicates an insertion slot ofthe coil end or a protrusion slot of the bus bar 302 a (R-phase input).Reference numeral 44 b indicates an insertion slot of the coil end or aprotrusion slot of the bus bar 302 b (S-phase input). Reference numeral44 c indicates an insertion slot of the coil end or a protrusion slot ofthe bus bar 302 c (T-phase input).

The terminals of the bus bars can be formed in various shapes. Forexample, when using pressure welding such as a connector, at least thecoil ends or the terminals of the input and output terminal block aredetachable from the bus bars. In this case, the mold unit is providedwith insertion slots for the terminals. When using screwing, at leastthe coil ends or the terminals of the input and output terminal blockcan be screwed to the bus bars.

Next, the connection between the non-intersecting bus bars, whichconstitute the external connection position change unit according to theembodiment of the present invention, and the coil ends will bedescribed. FIGS. 7A and 7B are a perspective view and a plan view of thenon-intersecting bus bars that constitute the external connectionposition change unit according to the embodiment of the presentinvention, respectively. FIG. 7C is a plan view of the three-phase coilsconstituting the three-phase AC reactor. An output terminal 13 a of thefirst coil (e.g., R-phase coil) 1 a is connected to the terminal 303 aof the first output terminal bus bar 301 a on the side of the first coil1 a. An output terminal 13 b of the second coil (e.g., S-phase coil) 1 bis connected to the terminal 303 b of the second output terminal bus bar301 b on the side of the second coil 1 b. An output terminal 13 c of thethird coil (e.g., T-phase coil) 1 c is connected to the terminal 303 cof the third output terminal bus bar 301 c on the side of the third coil1 c. An input terminal 14 a of the first coil (e.g., R-phase coil) 1 ais connected to the terminal 304 a of the first input terminal bus bar302 a on the side of the first coil 1 a. An input terminal 14 b of thesecond coil (e.g., S-phase coil) 1 b is connected to the terminal 304 bof the second input terminal bus bar 302 b on the side of the secondcoil 1 b. An input terminal 14 c of the third coil (e.g., T-phase coil)1 c is connected to the terminal 304 c of the third input terminal busbar 302 c on the side of the third coil 1 c. The non-intersecting busbars allow for easy obtainment of an insulating distance between the busbars of different phases while minimizing the height of the externalconnection position change unit, thus resulting in a reduction in sizeof the external connection position change unit. The external connectionposition change unit is not necessarily molded with a resin, but resinmolding facilitates the easy obtainment of the insulating distance andhence allows further miniaturization.

Next, the connection between the intersecting bus bars, which constitutethe external connection position change unit according to the embodimentof the present invention, and the coil ends will be described. FIGS. 8Aand 8B are a perspective view and a plan view of intersecting bus bars32 that constitute the external connection position change unit 3according to the embodiment of the present invention, respectively. FIG.8C is a plan view of the three-phase coils constituting the three-phaseAC reactor. The output coil end 11 a of the first coil (e.g., R-phasecoil) 1 a is connected to the terminal 33 a of the first output terminalbus bar 31 a on the side of the first coil 1 a. The output coil end 11 bof the second coil (e.g., S-phase coil) 1 b is connected to the terminal33 b of the second output terminal bus bar 31 b on the side of thesecond coil 1 b. The output coil end 11 c of the third coil (e.g.,T-phase coil) 1 c is connected to the terminal 33 c of the third outputterminal bus bar 31 c on the side of the third coil 1 c. The input coilend 12 a of the first coil (e.g., R-phase coil) 1 a is connected to theterminal 34 a of the first input terminal bus bar 32 a on the side ofthe first coil 1 a. The input coil end 12 b of the second coil (e.g.,S-phase coil) 1 b is connected to the terminal 34 b of the second inputterminal bus bar 32 b on the side of the second coil 1 b. The input coilend 12 c of the third coil (e.g., T-phase coil) 1 c is connected to theterminal 34 c of the third input terminal bus bar 32 c on the side ofthe third coil 1 c. In the example shown in FIGS. 8A and 8B, the busbars 31 a and 31 b partly overlap, and the bus bars 31 b and 32 a partlyoverlap. The partly overlapping bus bars allow the coil ends to protrudeas-is to the side of the input and output terminals, without shiftingthe positions of the coil ends, when the bus bars are connected to thecoils. In other words, the coil ends are normally situated on both endportions of each coil, and the partly overlapping bus bars eliminate theneed for shifting the positions of the coil ends. On the contrary, asshown in FIG. 7C, the non-overlapping bus bars require at least part ofthe coil ends to shift from the end portions to middle portions. Theabove embodiment describes an instance where the bus bars 31 a and 31 bpartly overlap, and the bus bars 31 b and 32 a partly overlap. However,the overlapping positions of the bus bars are not limited to the above,and other bus bars may partly overlap.

FIGS. 9A to 9C are plan views of the three-phase coils, the externalconnection position change unit, and the input and output terminalblock, respectively, that constitute the three-phase AC reactoraccording to the embodiment of the present invention. FIGS. 10A and 10Bare perspective views of the three-phase coils and the externalconnection position change unit that constitute the three-phase ACreactor according to the embodiment of the present invention before andafter assembly, respectively. As shown in FIG. 9A, the R-phase outputterminal 13 a of the first coil (R-phase coil) 1 a, the S-phase outputterminal 13 b of the second coil (S-phase coil) 1 b, and the T-phaseoutput terminal 13 c of the third coil (T-phase coil) 1 c, whichconstitute the three-phase AC reactor, are not aligned (apposed). In thesame manner, the R-phase input terminal 14 a of the first coil (R-phasecoil) 1 a, the S-phase input terminal 14 b of the second coil (S-phasecoil) 1 b, and the T-phase input terminal 14 c of the third coil(T-phase coil) 1 c are not aligned (apposed). Thus, when an externaldevice is connected to the coils (1 a, 1 b, and 1 c) of individualphases, the connection terminals of the external device have to besituated in accordance with the positions of the input and outputterminals of the coils of the individual phases, thus hindering easyconnection.

Against this problem, the three-phase AC reactor according to theembodiment of the present invention is provided with the externalconnection position change unit 3 between the coils (1 a, 1 b, and 1 c)of individual phases of the three-phase AC reactor and the input andoutput terminal block 2, in order to ease connection between the coilsof individual phases of the three-phase AC reactor and an externaldevice.

In other words, as shown in FIG. 10A, the R-phase output terminal 13 a,the S-phase output terminal 13 b, and the T-phase output terminal 13 care connected to the terminal 303 a of the bus bar 301 a on the side ofthe first coil 1 a, the terminal 303 b of the bus bar 301 b on the sideof the second coil 1 b, and the terminal 303 c of the bus bar 301 c onthe side of the third coil 1 c, respectively. The terminals of the busbars 301 a, 301 b, and 301 c on the sides opposite the terminals 303 a,303 b, and 303 c, which are situated on the sides of the first to thirdcoils 1 a to 1 c, (on the side of the input and output terminal block)are aligned. In the same manner, the R-phase input terminal 14 a, theS-phase input terminal 14 b, and the T-phase input terminal 14 c areconnected to the terminal 304 a of the bus bar 302 a on the side of thefirst coil 1 a, the terminal 304 b of the bus bar 302 b on the side ofthe second coil 1 b, and the terminal 304 c of the bus bar 302 c on theside of the third coil 1 c, respectively. The terminals of the bus bars302 a, 302 b, and 302 c on the sides opposite the terminals 304 a, 304b, and 304 c, which are situated on the sides of the first to thirdcoils 1 a to 1 c, (on the side of the input and output terminal block)are aligned. As a result, the apposition of the terminals of the busbars of the external connection position change unit 3 allows easyconnection between the coils of individual phases of the three-phase ACreactor and an external device.

Next, a method for connecting the external connection position changeunit and the coil ends will be described with reference to FIGS. 11A and11B. FIG. 11A is a plan view of a coil end insertion slot of theexternal connection position change unit 3 and the coil end according tothe embodiment of the present invention, and FIG. 11B is a sectionalview thereof. For example, as shown in FIG. 11A, the input terminal 14 cof the third coil (T-phase coil) 1 c, as a coil end, is inserted intothe terminal 304 c of the third input terminal bus bar 302 c on the sideof the third coil 1 c, as a coil end insertion slot, in the direction ofthe arrow to connect the coil end to the bus bar.

When the external connection position change unit 3 is connected to thecoils, as shown in FIG. 10B, the terminals of the bus bars 301 a, 301 b,and 301 c are aligned (apposed). As a result, as shown in FIG. 9C, it ispossible to easily connect the terminals of the bus bars 301 a, 301 b,and 301 c to the R-phase first output terminal 21 a, the S-phase secondoutput terminal 21 b, and the T-phase third output terminal 21 c of theinput and output terminal block 2, respectively.

In the same manner, as shown in FIG. 10A, the R-phase input terminal 14a, the S-phase input terminal 14 b, and the T-phase input terminal 14 care connected to the terminal 304 a of the bus bar 302 a on the side ofthe first coil 1 a, the terminal 304 b of the bus bar 302 b on the sideof the second coil 1 b, and the terminal 304 c of the bus bar 302 c onthe side of the third coil 1 c, respectively.

When the external connection position change unit 3 is connected to thecoils, as shown in FIG. 10B, the terminals of the bus bars 302 a, 302 b,and 302 c are aligned (apposed). As a result, as shown in FIG. 9C, it ispossible to easily connect the terminals of the bus bars 302 a, 302 b,and 302 c to the R-phase first input terminal 22 a, the S-phase secondinput terminal 22 b, and the T-phase third input terminal 22 c of theinput and output terminal block 2, respectively.

Next, a method for connecting the input and output terminal block 2 tothe external connection position change unit 3 will be described. FIGS.12A and 12B show an example in which the connection between the inputand output terminal block and the external connection position changeunit according to the embodiment of the present invention is performedby screwing. FIG. 12A shows a state before screwing, while FIG. 12Bshows a state after screwing. For example, after a hole formed in thebus bar 301 a is aligned with a hole formed in the first output terminal21 a of the input and output terminal block 2, a screw 51 a is screwedinto the holes. In the same manner, after a hole formed in the bus bar301 b is aligned with a hole formed in the second output terminal 21 bof the input and output terminal block 2, a screw 51 b is screwed intothe holes. In the same manner, after a hole formed in the bus bar 301 cis aligned with a hole formed in the third output terminal 21 c of theinput and output terminal block 2, a screw 51 c is screwed into theholes. As to the input terminals, in the same manner, after a holeformed in each of the input terminal bus bars 302 a, 302 b, and 302 c isaligned with a hole formed in each of the first to third input terminals22 a, 22 b, and 22 c of the input and output terminal block 2, eachscrew 52 a, 52 b, or 52 c is screwed into the holes.

The connection between the coil ends and the external connectionposition change unit 3 and the connection between the externalconnection position change unit 3 and the input and output terminalblock 2 may be performed by any of screwing and pressure welding using aconnector and the like. At least one of the connection between the coilends and the external connection position change unit 3 and theconnection between the external connection position change unit 3 andthe input and output terminal block 2 is performed by pressure weldingusing a connector and the like.

According to the three-phase AC reactor of the embodiment of the presentinvention, the coil ends of the non-apposed rectangular wire coils arechanged in position to be connected to an external device, as connectionparts arranged side by side, thus allowing easy connection to theexternal device.

Next, a method for manufacturing the three-phase AC reactor according tothe embodiment of the present invention will be described. The methodfor manufacturing the three-phase AC reactor according to the embodimentof the present invention includes a step of inserting the terminals ofthe bus bars of the external connection position change unit 3 on theside of the individual three-phase coils onto the coil ends to establishconnection, and a step of inserting the input and output terminals ofthe input and output terminal block 2 onto the terminals of the externalconnection position change unit 3 on the side of the input and outputterminal block to establish connection.

FIGS. 13A and 13B are exploded views of the three-phase AC reactor 10according to the embodiment of the present invention. FIG. 13A shows astate before the external connection position change unit 3 and theinput and output terminal block are connected to the three-phase ACreactor, while FIG. 13B shows a state after connection. FIG. 14 is aflowchart that explains the method for manufacturing the three-phase ACreactor according to the embodiment of the present invention. In stepS101, the terminals (33 a, 34 a, 33 b, 34 b, 33 c, and 34 c) of the busbars (31 a, 32 a, 31 b, 32 b, 31 c, and 32 c) of the external connectionposition change unit 3 on the side of the individual three-phase coilsare inserted onto the coil ends (11 a, 12 a, 11 b, 12 b, 11 c, and 12 c)to establish connection (see FIGS. 10A and 11).

Next, in step S102, the input and output terminals (21 a, 21 b, 21 c, 22a, 22 b, and 22 c) of the input and output terminal block 2 are insertedonto the terminals of the bus bars (31 a, 31 b, 31 c, 32 a, 32 b, and 32c) of the external connection position change unit 3 on the side of theinput and output terminal block 2 to establish connection (see FIGS. 13Aand 13B).

The above describes an instance in which the bus bars and the input andoutput terminal block are formed separately, but the bus bars and theinput and output terminal block may be integrated into one unit. Theintegrated structure can omit the step of connecting the input andoutput terminal block to the bus bars.

According to the method for manufacturing the three-phase AC reactor ofthe embodiment of the present invention, in a manufacturing process ofthe AC reactor having the non-apposed rectangular wire coils on theprecondition of automation, the coil ends of the three-phase AC reactorcan be connected to the input and output connection parts only byinserting the coil ends of the rectangular wire coils into the externalconnection position change unit, thus facilitating the automation of themanufacturing process.

The three-phase AC reactor according to the embodiment of the presentinvention allows easy connection to an external device, even when thethree-phase coils are arranged (apposed) neither in parallel nor in alinear manner.

What is claimed is:
 1. A three-phase AC reactor comprising: three-phasecoils arranged neither in parallel with each other nor in a linearmanner; an input and output terminal block having an input and outputunit having a parallel and linear arrangement; and an externalconnection position change unit disposed between a coil end of each ofthe three-phase coils and the input and output terminal block to connectthe coil end to the input and output terminal block.
 2. The three-phaseAC reactor according to claim 1, wherein the external connectionposition change unit is detachable from at least one of the coil end anda connection unit of the input and output terminal block.
 3. A methodfor manufacturing the three-phase AC reactor according to claim 1,comprising the steps of: inserting a terminal of a bus bar of theexternal connection position change unit on the side of each of thethree-phase coils onto the coil end to establish connection; andinserting an input or output terminal of the input and output terminalblock onto a terminal of the external connection position change unit onthe side of the input and output terminal block to establish connection.